Adelaide Metro in December 2007 Rainfall above average, and a month of temperature extremes.

Summary

Adelaide recorded above average rainfall for December, chiefly in one rain event. Temperatures were above average for the month as a whole, despite a cold lead-up to Christmas Day, and the month ended with a heatwave.

Rainfall

Adelaide's (Kent Town) rainfall for December 2007 was 37.2 mm recorded on 7 days, most of the total occurring in one rain event on the 21st of December. This is compared to the average of 27.6 mm on 7 days. Last year, 16.8 mm was recorded in December on 5 days. The driest December on record occurred in 1904 at West Terrace when no rainfall was recorded.

The total rainfall for 2007 was 464.6 mm in 114 days. In 2006 287.6 mm on 86 days was recorded. The annual average rainfall for Adelaide at Kent Town is 555.1 mm.

Temperature

The mean maximum temperature recorded at the South Australian Regional Office (Kent Town) for December 2007 was 28.5°C, which is 1.6°C above the December mean maximum temperature of 26.9°C. The mean December maximum last year was also 28.5°C, while the record December mean maximum was 29.0°C in 2003.

The month finished with a heatwave of three days with maximum temperatures greater than 40°C. This is the first time at Kent Town that there have been three days in December with maximum temperatures greater than 40°C. There were three days greater than 40°C in December in 1941 at the West Terrace station, and several other occurrences prior to this at that station.

The hottest maximum temperature recorded in the Adelaide metropolitan area was 41.8°C on the 30th at Parafield Airport, whilst the lowest was 18.0°C at Noarlunga on the 23rd.

The mean minimum temperature for December 2007 at the South Australian Regional Office (Kent Town) was 16.4°C, which is 0.9°C above the normal December mean minimum of 15.5°C. The highest average minimum is 16.9°C in 2003. Last December the mean minimum was 15.6°C.

The coldest minimum temperature recorded in the Adelaide metropolitan area was 8.7°C on the 10th at Edinburgh Airport, whilst the warmest night was 27.6°C at the Adelaide (Kent Town) on the 31st.

Notes

This statement has been prepared based on information available at
1 pm on Monday 31 December 2007.
Some checks have been made on the data, but it is possible that results will change
as new information becomes available.

Normals are long-term means based on observations from
all available years of record, which vary widely from site to site.
They are not shown for sites with less than 20 years of record, as they cannot then be calculated reliably.
The median
is sometimes more representative than the
mean
of "normal" rain.

The Rank indicates how rainfall this time compares with the climate record for the site,
based on the
decile ranking
(very low rainfall is in decile 1, low in decile 2 or 3,
normal in decile 4 to 7, high in decile 8 or 9
and very high is in decile 10).
The Fraction of normal shows how much rain has fallen this time as a
percentage of the long-term mean.